Automatic thermostat-adjuster.



J. w. FROST. AUTOMATIC THERMOSTAT ADJUSTER.

APPLICATION FILED DBO. 4. 1908. 950,54 Patented Mar.1,1910.

2 SHEETS-SHEET 1.

J. W. FROST.

Patented Mar. 1,1910.

2 SHBETB-BHEET 2.

- To all whom it may concern:

JOSEPH .W. FROST, OF WASHINGTON, DISTRICT OF COLUMBIA.

AUTOMATIC THERMOSTAT-ADJUSTER Specification 01' Letters Patent.

, Patented Mar. 1, 1910.

Application filed December 4, 1908. Serial No. 466,000.

Be it known that'I, Josnrn W. Fnos'r, a

v citizen of the United States, residing at Washington, in the District of Columbia, have invented certain new and useful Imrovements' in Automatic Thermostat-Adusters, of which the following is a specification.

It is well understood by those versed in the art that correct manual adjustment (or ad ustment by hand), of certain well known forms of electric thermostats, namely, those cuit, is extremely difficult because of the very small movement of the thermal element under the influence of the temperature usually sought to be guarded against. Thermostats of a certain ind, like that shown in Figure 2 (to be hereinafter fully described), are usually adjusted -to the predetermined degree, by being first placed in a hot box, the temperature of which is slowly increased up to the desired point,.and, while under theinfluence of such degree of temperature, having ,the electrodes slowly turned to contact by means of. an adjustable set screw which usually forms one of the said electrodes. This fact, the small movement of the thermal element, together with other adverse conditions such as at times the over-tightness of the set screw in its bearing, renders it very diflicult to adjust them accurately and precisely by hand; which however steady, is powerless to cope successfully with such delicate conditions.

The object of this device or invention is to provide meanswhereby the screw driver, instead of being operated by hand to turn the set screw to contact and no more, is operated by the shaft of a clockmovement which is stopped electrically and instantly when the contacts are. made.

' Fig. 1 is a side view of the automatic adjuster showing the operating position of same. Fig. 2 is a sectional view of a well known form of thermostat showing the operating connection between the same and the adjuster, and Fig. 3 is a face view of the automatic adjuster, showing the electrical connections.

- s ring In further explanation of the preliminary statement, I W111 first briefly describe the thermostat shown in Fig. 2 which this de vice is particularly adapted to operate in connection with. v

The sectional view shown includes a circular porcelain base 1, molded in such a manner as' to contain an annular recess 2 and a flat annular shoulder 3, together with the necessar holes for fastening the other parts to the use. I In the circular recess and against the shoulder is loosely inserted a concave-convex metallic diaphragm 4, which by means of screws 5, 5, 5, and nuts 6 (only one shown) is bolted firmly to the base so that in expanding it warps or buckles in the direction of its convex side to contact with the point of set screw 7, which completes the circuit; the disk 4: being one electrode and the set screw 7, the other. A sectional view of a shield 8 is shown, the same 7 which is hin ed at 11, so as to permit it to be raised an lowered for the purpose to be referred to later in these specifications. Upon this hin d portion 10, is suitably mounted a cloci movement-12, the escapement or pendulum of which 13, is controlled by the armature lever 14 which armature lever 14, is in turn controlled, as shown, by the electromagnet 15; the coils of which 20 20 see Fig. 3) are secured to each other an to t e base 10 (Fig. 1) by the yoke 21, the bracket 22 and the screws 23, 23. The device shown is a. well known form of electromagnetic clockwork tripping device, used in connection with burglar, fire and other alarm signals. The train of Wheels of the clock-work and the pendulum of the escapement, are driven or actuated by the coiled 16, connected to the main shaft 17. 0 this main shaft is fastened by means of v the disk of the thermostat.

the pin 18, a screw driver 19, for turning the set screw 7 (Fig. 2) down to contact with The screw driver shown is the well known form of ratchet screw driver which it is preferred to use. An ordinary form of two-point switch is shown by 24. This is included in the cir- I cuit of the coils 20, 20, (Fig. 3) -and the battery 25, and is used to control the circult of same.

InFig. 1 the device 1s shown as being 1n .0 eration; that is, the parts are shown in work frame which supports the gearing fastened to the wood base by means of the screws 26, 26, 26, and also the pendulum 13 held in check by the armature lever14, with the armature retracted from the magnet by means of the spring 27. The circuit is described as follows in connection with Flg. 3: from onei pole 28, of the battery 25, through wirei29 to the hinge 30, and from thence by connector 31, to and through the magnet coils 20, 20, to connector 32, to and through hinge 33 by wires 34 and 35 to the heel point 36 of the two-point switch 24. From thence, when said switch is closed the circuit runs by wire 37 back to the opposite pole 38,| of the battery. This describes the principal circuit of the device. A shunt circuit, normally open as shown, runs as follows: from hinge 30, wire 39, to the metallic clock movement frame of which. the screw driver 19 is a. part; here the shunt cirucuit is open. Another branch of this shunt circuit runs from connection 40 by wire 41 to contact button 42. This contact button and the frame to which it is connected, co'nstitute the well known open circuit burglar alarm spring. It is evident that'when the screw driver 19 comes into contact with the button 42, a shunt or short circuit is completed cutting the current from battery 25,

off from the magnet coils 20, 20.

The operation of the device is as follows: The face of the thermostat, as shown at Fig. 2, and which consists of the metallic shield 8, in electrical connection with the thermostatic disk 4, is pressed a ainst the button 42, leaving the set screw or its slot, exposed for connection with and operation by the screw driver 19, after the hinged base 10 is turned down, to the position clearly shown by Fig. 1. The screw driver is then connected to the set screw, (Fig. 2) and the switch 24 is closed as shown at" Fig. 1. The set screw point at this time is separated from the thermostatic disk which is at the same time under the influence of the predetermined degree' of adjustment. The switch 24 being closed as shown in Fig. 1, the armature of the magnet 15 andv armature lever, are attracted toward 'the coils, releasing the pendulum 13, which allows the clock-work to run turn. The circuit which causes this operation has been already described. When the point of the set screw 7 comes into contact withthe disk, the previously described shunt circuit around the ma net coils is completed, the currentdiverted rom said coils, the armature retracted by the coiled spring 27,

The switch 24 is then opened and the thershaft. The spring contacts 44, 44, fastened pose of making more reliable the electrical contact between the two parts of the hinges 30, 33, when the hinged base 10 is turned down as in Fig. 1, to operative position. Two brackets, 45, 45, are also shown in Fig. 3 for the purpose of furnishing a rest for same when the hinged base 10, IS in the po-- sition shown in Fig. 1.

It is plain that this invention is not restricted to the use of the particular form of thermostat here shown, or in fact to a thermostat at all; but may, respectively, be used where the adjustment is efiected by means of a set screw or its equivalent, or in connection with any other electrical device of a similar character;

1. In an electric checking device, the combination of the motor 12, controlling a screw driver 19; an electromagnetic device in circuit with a generator, 25, which actuates the said motor; means for starting the motor; and circuits and-connections, substantially as described, for checking the said motor at a predetermined point.

2. In an automatic electric adjusting device, the combination of the motor 12, controlling a screw driver 19, an electro-magnetic device which controls the operation of said 'motor, an electric generator, (25), in circuit with the .electromagnets of said controlling device, a switch (24), normally open and also included. in sa1d circuit; a shunt around said magnet coils the terminals of which shunt are connected respectively with the screw driver and a contact button 42, whereby on the closing of the switch the mechanism including'said screw driver will be actuated and whereby on contact between the same and said button said electro-magnets or its coils will be shunted and the sa1d scribed.

and the clock movement is suddenly stopped.

mostat removed from connection with the to the hinges 30,33 (Fig. 3), are for the pur- Whatis claimed is v and the main (screw driver) shaft 19 to I in connection with any form of thermostat mechanism checked, substantially as demeans (switch 24) for starting the motor,

3. In an electric adjusting device, the comering the driver, as by hinges 30-33, subbination of the motor 12, controlling a driver stantially asdescribed. 10 19; an electromagnetic device in circuit with In testimony whereof I have affixed my a generator 25 which controls the motor; signature in presence of two witnesses.

JOSEPH W. FROST.

and circuits and connections substantially as \Vitnesses:

described, for checking same at a predeter- J. G. MOMAHON,

- mined point; and means for raising and low- ELIZA A. FRos'r. 

